Students learn about the law of cosines. The tutorial consists of a definition, examples, and practice problems to check for comprehension.

Use the law of cosines to calculate unknown angles or sides of a triangle. In order to calculate the unknown values, you must enter 3 known values.

[Free Registration/Login may be required to access all resource tools.] Looks at triangle problems where you are given the area and must use trigonometry to find unknown sides or angles.

This site really is a crash review on trigonometry! Formulas, functions - you name it, it's covered! Also includes self quizzes for practice.

College professor Dan Bach reviews basic trig concepts, including trig functions, right triangles, circles, radians, and polar coordinates. Site includes animated graphs and detailed examples.

This site discusses the theorems and other findings which are directly related to the fundamental Pythagorean theorem. Be sure to click on the link to information on Pythagorean theorem to find several proofs of the theorem.